Dairy Shed Energy Efficiency – A Healthy Taieri Project

The Healthy Taieri project worked directly with dairy farms in the Taiari / Taieri catchment to assess dairy shed energy efficiency, identifying potential improvements and providing recommendations for investment decisions that can be shared with others in the catchment.

Support from the Healthy Taiari Project enabled energy audits on dairy sheds on seven farms on the Taiari Plains. These audits resulted in recommendations for improving the energy efficiency of the dairy sheds, as well as assessing electricity supply contracts to identify where cost savings could be achieved.

In the wider scheme of dairy farm, electricity typically constitutes only a small amount to the total operational costs, in the range of 0.5% – 2% (excluding irrigation). For this reason, time and effort is often spent on reducing costs in other areas of the business. All of this means there are often energy and cost-saving opportunities at the dairy shed which have not been investigated.

Using evidence from past studies, auditors were able to identify opportunities in all areas of the dairy shed for the participants of the programme. From over-sized hot water cylinders, uninsulated milk vats, heat recovery, and electricity tariff adjustments, thousands of dollars in savings per year were identified for each of the participants in the programme. Heat recovery is the biggest opportunity to improve efficiency for all sheds visited.

A presentation given to DairyNZ members on the programme and the possible opportunities for energy and cost savings is available to download here (2MB).

Key findings from the audits were:

  • Heat recovery, heat recovery, heat recovery!
  • Wrap your vat, especially if you are on second-day collection.
  • Wrap your low-pressure refrigerant line, a pool noodle and electrical tape is not pretty but quite effective.
  • Solar collection from solar water heating or Photovoltaic is not a good fit for dairy sheds in the south as the peak electrical demands of milking do not align with typical solar generation times.
  • Ask your retailer for your half-hourly demand data, use it to check if your connection capacity is appropriate – Farms typically have multiple connections and merging these will almost always save money.
  • If something is hot or cold to the touch, insulate it.

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